As it can easily hook on to clouds and the like, I will be using my penis as a grappling hook and safely swing from safe zone to safe zone, high above the heads of zombies. I may possibly also flip a few of them the bird.

Don't really see how that'd matter all that much, considering all the lootable buioldings etc.

You really want to stop for fuel every 20 feet?

Imagine the stereotypical coal-powered train and massive trailer the size of a rail car full of coal. Now imagine that that's only enough to keep that train moving for a few hundred kilometers, at best. And then imagine that coal stores more potential energy than anything else readily available and combustible, save petroleum-based fuels.